Lifting mechanisms have been successfully used for a number of years to lift various items in various situations. One particularly popular use is to lift beds and/or seating units in vehicles and other situations where space is limited. The '881 patent identified at the end of the description discloses a number of lifting mechanisms that can be used for a variety of purposes.
Although conventional lifting mechanisms have enjoyed a significant amount of commercial success, they can still pose problems in certain situations. One of those situations occurs when the lifting mechanism is used to lower an object onto the floor or onto a support base positioned on the floor. The problem is that the object is fixed to the lifting mechanism so that it must be lowered to exactly the right height to be fully supported by the floor. If it isn't lowered far enough, then it won't be supported by the floor. It will be supported primarily or entirely by the lifting mechanism. If it is lowered too far, then the lifting mechanism pushes the object downward into the floor, which increases wear and tear on the lifting mechanism.
These problems are magnified when the object is configured to closely correspond to a support base positioned on the floor. Any misalignment will create gaps between the object and the support base, which indicate that the object is not fully supported by the support base and is at least partially supported by the lifting mechanism.
These problems were addressed in one of two ways in the past. The first way is to mount the lifting mechanism in exactly the location required for the object to be properly supported on the floor or by the support base. This is time consuming and unforgiving. There is little or no room for error. The second way is to provide some way to adjust the position of the object when it is in the lowered position so that it is properly supported by the floor or the support base. This introduces additional mechanical complexity to the mechanism and/or object and requires an additional adjustment procedure after everything has been mounted. Both increase the cost and/or time required to manufacture and/or install the system.